Technical Abstract:
Recombinant chicken interleukin-2 (IL-2) promotes the growth of T cells in vitro and enhances NK-cell activity in chickens. Stimulation of IL-2- dependent T-cells with Con A induced interferon-gamma (IFNg) and IL-2 mRNA transcripts whereas stimulation with rIL-2 induced only IFN-mRNA. Subcutaneous injection of rIL-2 RNA to day-old chickens increased the percentage of cells which express the CD8 and TCR antigens in the spleen. Chickens which were orally infected with Eimeria acervulina showed a significant enhancement of IL-2 mRNA transcripts in the spleen and intestine and increased percentage of T-cells in the duodenum following both primary and secondary infections. These results indicate that host immune responses to E. acervulina involve an up-regulation of IL-2 secretion and an increased duodenum T-cells. 1